The Biostatistics and Database Management Core will provide database and statistical support to the Mayo Alzheimer's Disease Research Center (ADRC) Projects and Cores. To this end, our specific aims are: Specific Aim 1. To develop and maintain a relational database housing the longitudinal clinical and neuropsychometric data gathered by the Clinical Core. Specific Aim 2. To provide database support and biostatistical consulting support to the Projects and Cores. Building upon the existing Mayo ADRC relational database structure, database management staff will expand the Clinical Core psychometric and clinical exam database to accommodate new forms introduced by the Clinical Core and new forms mandated by the NIA (the expanded standard clinical data set). Various improvements to our database will be implemented, including a web-based data element dictionary and electronic data audit capabilities. The Clinical Core database will be linked to imaging, genotype, neuropathology, and DNA and plasma inventory databases, and data management staff will support data requests by Core and Project investigators. Biostatisticians will support Core and Project investigators in study design, analysis, and interpretation. The Biostatistics and Database Management Core will provide database support and dedicated time for statistical consulting to all of the Cores and Projects. Sharing of database and statistical personnel will allow us to efficiently support various projects and ensure that biostatistical consultants familiar with Alzheimer's disease and with the details of the Mayo Clinic ADRC are available to Cores and Projects.